You are demeaning yourself. That will make it that much easier for me to ignore you completely.

Where is the guy that wanted my head and what did you do to him?

Some of them aren't even science — Michael

@VagabondSpectre criticized amply and thoroughly my approach. One of his main arguments concerns the photons that are radiated sideways through a (collimated) beam. I must admit that I am curious about where he gets his conviction from.

What I know of light going in one direction, is that electric and magnetic fields are perpendicular to this direction, in which the photons are propagated.

These side waves, or fields, are usually depicted the way a water wave is: particles going up and down a very limited distance, and a disturbance moving along the axis of direction.

I would be very much obliged if somebody gave me some links or references for VagabondSpectre's interpretation.

With all due respect, your view shows a very narrow interpretation of philosophy of science. There is certainly a technical aspect to all the questions I pose, but they also concern the way science looks at the world, and what is considered as proof.

Interpreting my posts as technical questions which are in need of technical answers is ignoring the epistemological and even metaphysical underpinnings of many scientific issues.

Some people have taken offense at my view of Cosmology as "metaphysics for scientists", or "metaphysics with mathematical formulas", I suppose you would agree with them.

No worries. If someone posts something controversial, I'll delete it. — Hanover

X-)

Vibrations and Visibility

This drawing is supposed to explain how light is reflected in different directions.

It is in fact a formalization of the more popular explanation presented by Bragg to a general audience.

Here is what I still find puzzling:

Whether light is reflected vertically (towards the mirror), or horizontally (towards the camera), it should be visible from both perspectives.

Imagine bright rays shining vertically, and others shining horizontally, wouldn't you face the same bright rectangle in both cases?

I still think that one or two subforums where "non-standard" posts could be moved would be preferable to deletion. — SophistiCat

You are advocating a Kiss of Death policy.

All ideas are equal, but some ideas are better than others.

edit: All ideas are equal, but some ideas are more equal than others.

Thank you for your support, I really appreciate it.

I was in fact defending science against bigotry.

I am glad I am given the opportunity of expressing very controversial views.

but maybe Hachem and others would like to defend themselves against the charge of idiocy/crackpottery. — Baden

Science thrives through criticism and heretics. Giordano Bruno was burned alive, Galileo had to recant. Einstein doubted the Newtonian time and space, etc.

I will certainly not claim to belong in this illustrious company, but I think that the way many people look at science is indeed religious (pace Vagabondspecter).

What is now considered as truth can become obsolete tomorrow. And that is only possible through discussion and criticism.

It is good to defend extant theories. The burden of proof should always lie by the challengers or contenders. But ridiculing people because their views do not stroke with what science now says is true is unworthy of a scientific mind.

I do not claim that I am in possession of the truth either. But I do have doubts and questions. That is what I attempt to argue in my threads.

Referring to the scientific status quo is in itself not enough. It that were the case, there would never be any progress or so-called scientific revolutions.

It is very possible, maybe even probable, that my views and analyses will simply be discarded in time and proven utterly wrong. In the process, something might be learned, at least by me and other lost readers, and there might be even positive consequences because even wrong critique can lead to rightful questions.

If we knew how the future of science looked like, we wouldn't need science anymore.

Is Red + Green + Blue White?

It seems so obvious. Who would be stupid enough to doubt such an obvious empirical fact?

But then, what would happen if you used a non-white screen?

Is Darkness the same as Black?

Close your eyes, and you will certainly notice that your not looking a a black wall.

The absence of light is quite different from blackness, even if they share one very fundamental property: lack of visibility.

One very important fact in cognitive science is that eye cells are never in complete rest. There is always a threshold of activity even in complete blackness.

I personally think that comes because we are able to see darkness or blackness. There is no situation, except maybe when we are closing our eyes and it is also totally dark, where our eyes are not reacting to what is happening around them

So, yes, when the sun disappears, everything turns dark. But that does not mean that we stop seeing.

Biological creatures have at least to register the disappearance of sun light, and for us, of all colors.

We would be hard put to justify the transition from light to dark as any different than the transition from red to blue.

Also, darkness only looks black because of the way our eyes are built. With different goggles, darkness could become red, or violet, or a shade of gray.

Inside the Camera obscura (3)

There remains at least one question unanswered.

How come we get practically the same pattern with one slit?

Here are some preliminary suggestions.

Imagine walking at night along the road on a full moon. The moon seems to be following you. That is of course a simple optical illusion because the distance you can walk at anytime is infinitely smaller than the moon is large, and the distance separating you from it.

What is important is that, each time, you see a complete moon, and it is always as sharp.

If we replaced you with a camera which would be moved only microns at a time, the result would still be the same: one sharp moon for each position.

I do not think you could find a position, however close to the preceding one, that would show you a double or unsharp image.

In other words, wherever you are, you see one moon, and one moon only.

It does not really matter how that happens since that would only bring up an undesirable polemic.

When a grating is used, the opaque bands take care of the dark spots.

But we also know that the grating can be made invisible, as good as absent, without changing the image.

Whether the grating is present or not, different copies of the same object could be projected on the screen, depending on the size of the sensors and other technical properties.

Inside the Camera obscura (2)
The distinction between the retinal image and the projected image can hopefully help us understand why a laser beam directed through a (multiple) slit creates the images we know with bright and dark spots.

Imagine your retina as wide as the screen, and looking at the grating.

However you move your eye, or move through the camera obscura, you will see the beam through at least one slit at a time.

But you won't be able to see it through the gaps between the slits. They will be represented as dark lines or bands, just like the window grating on the upper floor of my building.

The difference between this picture, and the ones taken with a grating, as that of the bookshelf and the outside scene on one hand, and that of the laser beam on the other, is that the latter does not fill the entire width of the visual scene, but only a very circumscribed location.

What we are seeing therefore is each time the same beam, but then through another slit, with spaces in between them.

Only one beam image

Try as I may, I could not, using the grating, get the nice lineup of bright and dark spots when directing the laser beam through a pinhole lens, or even through an open body. Changing the distance and the exposure time did not change a thing, and I thought that I was making a mistake somewhere.

When I held the same slide in my hand and pointed the laser beam through it, I got the same image one sees in all clips and textbooks.

I then realized that the camera sensors did react somewhat like a retina. They took a picture of the laser mouth through the slit directly facing the camera. By shifting the camera slightly to the right or the left, another image of the same laser was taken.

The central image overwhelmed the other parts, and I had to reduce the exposure time drastically to get other, smaller, red points representing what I think was the laser beam. But the points were, as a consequence of the reduced exposure, not very detailed.

I also got sometimes more than one very bright spot, which I think was more a matter of false reflection and bad centering of the beam than anything else.

I am therefore left with the necessity of interpreting unclear images, or rather, relying on the ones usually used in this kind of experiments.

I do not believe in the theory of constructive and destructive interference. I think it is unnecessarily complicating some very simple facts:

Light has to go through splits that are separated by opaque bands, We see bright and dark spots. Why should it surprise us?

The dark spots are only visible under certain circumstances, like my pictures show.

The wider the object or the scene is, the less visible the grating will be,

But in the case of a localized light source, the grating will be prominent, and we will have the pattern that has puzzled every scientific mind since Newton.

I'd rather have no responses that dishonest responses. I never say there should be a link, only that if photons were propagated in all directions, that there should be a reaction of the matter between us and the beam. For instance, chalk dust should light up.

It does not, and your answer is well known enough. No use to repeat it to me. I say it does not light up for the simple reason that there are no photons going our way. What makes us see object is still a puzzle, but the contemporary theory of light does not convince me.

But you already knew that.

Now, if you won't answer to my challenge, and that is, to keep it simple:

How do you explain the pictures I made of a laser beam that look so much like Newton rings, or cases of interference?

Face my empirical queries or give it a rest.

Absent Gratings

How easy it is to make gratings disappear is shown here with the following two pictures taken from the upper floor of my building.

The black circles, vignetting, is due to the fact that I am using a so-called DX objective, one made for crop cameras, with a full frame body (24x36 mm). The vignetting can be safely ignored.

The first picture is taken with the zoom set on wide angle 20 mm, while in the second it is set at the telelens position of 270 mm.

Wide angle



Telelens

Please provide evidence that shows we can see collimated beams of light in a vacuum... — VagabondSpectre

You are really pathetic in your avoidance strategy. Please do not waste my time anymore.

and at 2:07-2:09 you can see the cloud of talcum powder reflecting the normal ambient light when he blows it. — VagabondSpectre

But we see the beam not only from that place, but from anywhere!

why are you procrastinating?

I am sure I could formulate my ideas better, more precisely, more carefully.

I am also certain that I am far from knowing everything there is to know about physics, or even about Optics.

But I am presenting you with empirical claims. The wet dream of every scientist, and you keep babbling about generalities?

https://youtu.be/FVpPU4NIJh0
around 1:55 mn. You can see the beam, but no link to the subject.

But then, that was because the photons are invisible and too few, right?

edit: no link to the camera either that is filming all this.

stop trying to hit me and hit me!

what are you afraid of?

Why do you claim that laser beams are themselves visible? — VagabondSpectre

not me no how

Because I already did, while you refuse systematically to discuss my empirical objections.

You prefer, like everybody until now, the safe discussion where your are exposing the "scientific" theory while pushing me in the weirdos' corner.

I will pass and not answer until you decide to take my objections seriously, not in a general way, since we have already done that.

Why don't you comment on my pictures concerning double slit, newton rings and interference? That would be very precise and empirical. Your chance to show that I just don't get it.

Let us give up the pretension that we could ever agree on even the simplest of tests.

Let us be clear on the test, and I will keep searching.

1) The subject shines a beam of light away from him at another object (in this case a lens).
2) He blows a handful of chalk dust in the air to make the beam visible.
3) the beam becomes visible, but no dust linking the beam to the subject is visible.

Agreed?

I have done the test, and I have seen it done on Youtube. I will give you the link as soon as I find it back.

"gospel" in this context has no religious connotation.

I do not feel like repeating our long and boring discussion where you stick to the official theory and I have to defend myself.

I thought we could avoid it by trying to be as objective as possible and devising empirical tests like the one I proposed, and of which you deny that it is even possible.

I notice that all you are doing is reciting the Optics gospel. You are not answering my question which could put an end to this sterile discussion.

I am offering an empirical test, all you do is repeat what is in the textbooks.

It's been long proven that you cannot see photons without having them enter our eyes or else through some form of "detector" (i.e: something for them to strike) — VagabondSpectre

I find this a very strange assertion in this context. We are talking about visible light, like for instance a beam of light directed towards or away from us. We can see this beam of light if the medium allows it.
As for instance in a swimming pool where the water is not "pure".

I have no trouble with the idea of invisible photons that only detectors could see. But we are talking about enough photons to create an image on our retina. Wherever we stand. Still you persist in your affirmation that they will remain invisible and that the area where we stand will remain utterly dark.

What if we you were to spray some chalk dust around you? Would the chalk dust become visible?

I would consider that as an empirical test for my analysis: if the dust become visible, then somehow photons are reaching the dark place of the observer.

I can tell you that It is very improbable. You will be able to make the (laser) beam visible, but not the photons leaving the beam and impinging on your retina.

Of course, if you think that even the dust would remain invisible, then I wouldn't know anymore what to tell you.

Inside the Camera Obscura

You can either imagine yourself very small, or the camera obscura very large. Whatever suits you.

You are standing with your back against the wall, and looking through the opening in front of you.

There are two distinct images we have to consider.

1) The retinal image of the outside scene, which will be of course inverted, allowing you to see the outside scene the normal way.

2) The image projected through the opening on the wall against which you are standing. This image will be much larger than your eyes, and probably overflow all around you. That is an image you only can see if you change position and face the wall.

The question now is: will making the opening smaller make both images darker, or only the second one?

You should know my answer by now.

We now know from cosmology — bill harris

That is the whole issue right here. Cosmology is metaphysics for scientists.

But then again, another general objection, a show of loyalty and no attempt to look at the issues themselves. I understand if you feel you have nothing to say on these problems, but please do not then decide for others what the nature of these problems is.

,

Now this, of course, is not a philosophical problem, but rather one of mechanical cause whose solutions will be found within the context of the science itself... — bill harris

Einstein and Bohr had to change their view of reality, space and time. And not (only) in a technical way.

Am I on the right track? — t0m

Certainly. And I am curious about how you look at it.

Not interested in

double slit experiment?
Newton rings?
Interference?
Optics?
Other problems in Physics?

No problem. Just don't waste my time and I won't waste yours. If all you can do is name calling and appeal to authority, then I am not interested.

I would kindly suggest you stop reading my threads since they only seem to aggravate you.

I know what is said about polarization. It just does not convince me.

I see you fall back on the same general strategy I have been facing until now.

Let us say I am wrong about my views considering Relativity and Quantum.

Let us say I am wrong considering the theory of the dual nature of light.

I make, even less than you, claims about my physics knowledge.

When we have established that I have no credentials to speak, or at least to be taken seriously, I hope you will find time to answer the specific questions concerning interference, newton rings and double slit.

I would be very interested in your explanation of the pictures which you can of course take yourself with a digital camera to make sure they were not photoshopped.

In other words, let us leave the secure space of epistemology and tread into one that should be dear to you: empirical knowledge.

Philosophy joke of the day:

Communism. — Posty McPostface

Posty McCarthy?

who u callin' kids, girl? Dobe to you too!

I'll keep my eyes open and my lips ready.
edit: my ears too.

guy says to hero de Niro: it is not bribery, I am now free and give you this money belt freely.
- how much is in there?
- in the neighborhood of $100.000.
- it's a nice neighborhood.

nice talent.